Loose-leaf binder.



PATENTED JULY 25, 1905.

. S. H. MITCHELL. Y LOOSE LEAF BINDER.

APPLICATION FILED ooT.15,19o4.

NITEn sTATEs PATENT OEEICE.

f LOOSE-LEAF BINDER.

Speccation of Letters Patent.

Patented July 25, 1905.

Application filed October l5, 1904. l Serial No. 228,532.

To @ZZ whom, it may concern,.- YBe it known that I, STEPHEN H. MITCHELL,a citizen of the United States of America, residing at Chicago, in thecounty of Cook and State of Illinois, have invented certain new anduseful Improvements in Loose-Leaf Binders, of which the following issuch a full, clear, and exact description as will enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, forming a part hereof.

This invention relates to loose-leaf binders, and has special referenceto that type of binders in which a double-threaded rod or screw 1iOsemployed to spread the sides or bindingars.

The principal object of the invention is to provide a construction bywhich a short key may be employed, thereby applying the operating powermore directly and preventing twisting of the shank or the key. Thisobject is attained by the use of the construction illustrated in theaccompanying drawings; and the invention consists in certain novelfeatures of the same, as will be hereinafter first fully described andthen particularly pointed out in the claims.

In the drawings just mentioned, Figure 1 is an elevation of a binderembodying my improvements. Fig. 2 is a similar view, partly in section,showing the bars separated-more than in Fig. 1. Fig. 3 is a verticalsection through the operating-rod. Fig. 4 is a detail end elevation, andFig. 5 is a detail sectional View showing a modification.

The bindingbars 1 are formed integral with or secured to the back 2,which consists of two overlapping plates, as shown and as will bereadily understood. The ends of the back-plates are turned forward andmade to form continuations of the binding-bars, so as to inclose theedges of the leaves held by the binder. The end of the lower back-plateis provided at its upper edge with an inwardlyprojecting lug or tooth 3,which coacts with a lip 4 on the end. of the upper back-plate to preventthe back-plates being moved so far as to be entirely separated. The endof the upper back-plate is provided with a grooved portion or guide 5,which engages the edge of the end of the lower back-plate, and therebyaids in securing an even movement of the two plates, the lip 4 beingformed at the lower end of this guiding portion.

Between the two bindingbars are telescopic posts 6 of the usualformation and a central operating connection. This operating connectionconsists of two internally-threaded stems or posts 7 adouble-threadedrod or screw 8, and a driving-arbor 9. The posts 7 approach each otherfrom the inner faces of the binding-bars and one of them is providedwith an extension 10, which fits telescopically over the other post, sothat the screw will be covered in all adjustments of the binder and oilor dirt prevented from coming into contact with and soiling the sheets.The said posts are internally1 threaded in opposite directions, and theends of the right and left threaded rod or screw 8 engage the threadedbores, so that when the said rod or screw is rotated the posts or stemswill be caused to move in opposite directions.

The upper portion of the rod or screw 8 is constructed with an angularsocket 11, in which is fitted the driving-arbor or turningbar 9. Thisturning-bar 9 is provided near its upper extremity with an annularflange or collar 12, which rests in a bearing 13, formed in the upperbinding-bar, and over this collar or iiange a keeper 14 is secured uponthe binding-bar, so as to hold the turning-bar against longitudinalmovement. The end of the turning-bar is extended slightly beyond thekeeper 14 and adapted to be engaged by a key or wrench 15.

In the modification shown in Fig. 5 the socket 11 of the screw iscircular, and the turning-rod is circular in cross-section and isprovided with a longitudinal groove or keyway 16, which is engaged by aradial pin 17, secured in the end of the screw..

The loose leaves to be held by the binder will of course be notched topass around the posts. After they are inserted between the sides of thebinder the key 15 is applied to the end of the turning-bar 9 and isrotated, as will be readily understood. The motion thus imparted to theturning-bar is transmitted directly to the double-threaded screw, andthe hollow stems or posts are thereby caused to approach, so as to drawthe sides of the binder together and clamp the leaves. course to removea leaf the turning-bar will be rotated in the contrary direction.

. It will be observed that the key is not applied directly to thedouble-threaded screw, and consequently does not travel with the screw,so that an exceedingly short key or wrench may be used. The provision ofthe turning-bar, furthermore, aids in maintaining the screw on astraight line, so that the movement will be even and steady, andconsequently easier than in the devices heretofore employed, in whichthe screw vibrated more or less, and thereby created greater friction.In the devices heretofore employed the arrangement has been such that akey having a long shank was needed, and the result was that the shankwas frequently twisted. The inconvenience of keeping a large key insafety was also considerable.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is Y 1. In a loose-leaf binder, the combination withthe sides or clamping-bars, of internallyf threaded posts extendinginward from the inner faces of the same, a double-threaded screwengaging the bores of said posts, and a turning-bar journaled in one ofythe clampingbars and adapted to actuate the said screw.

2. In a loose-leaf binder, the combination with the sides orclamping-bars, of internallythreaded posts extending inward from theinner faces of thesame, a double-threaded screw engaging the bores ofsaid posts and having a socket inone end, a turning-bar fit-- STEPHEN H.MITCHELL.

Witnesses:

EDWIN SHIELDs, C.l MITCHELL.

